Regulated rectifier circuits



June 8, 1937.

R. P. JUTSON ET AL 3,382

REGULATED RECTIFIER CIRCUITS Filed Dec. 21, 1935 RP. JUTSON fA/l/ENTORs' D E TRUC/(SESS A T TORNE V Patented June 8, 1937 UNITED STATES PATENT OFFILCE BEGULATED RECTIFIER CIRCUITS Application December 21, 1935, Serial No. 55,5

7 Claims. (Cl. 175-363) This invention relates to rectifier circuits and particularly to regulated rectifier circuits.

One object of the invention is to provide a three-element space discharge rectifier between an alternating current supply circuit and a load circuit that shall have the phase of the potential impressed on the grid varied'in an improved manner with respect to the potential impressed on the plate to maintain the rectified voltage con- 1 stant.

Another object of the invention is to provide a control circuit having a three-element space discharge rectifier connected between an alternating current supply circuit and a load circuit and a phase shifting bridge having one arm composed of a material with a negative temperature reslstancecoefiicient and connected between the supply circuit and the grid of the rectifier that shall control the temperature of the bridge arm having a negative temperature resistance coefficient inversely according to the rectified voltage for governing the bridge and the rectifier to maintain the rectified voltage constant.

A further object of the invention is to provide a control circuit of the above-indicated type having a phase shifting bridge with an arm of silver sulphide that shall be heated inversely according to the rectified vo1tage.-

When a rectifier is connected between an alternating current supply circuit and a load circuit it is desirable to have compensation made not only in accordance with the variation in the voltage of the supply circuit, but also in accordance with variations in the load on the load circuit so that the rectified voltage may be maintained substantially constant.

According to the present invention a threeelement space discharge device which is preferably of the gas-filled type has the plate circuit thereof connected between an alternating current supply circuit and a load circuit. The load circuit may have a battery floated across it. The grid of the space discharge device is supplied with alternating potential from the supply circuit by means of a phase shifting bridge circuit. One

arm of the bridge circuit is composed of silver su1-' phide which has a strong negative temperature resistance coefiicient. The bridge arm composed of silver sulphide is heated inversely according to the rectified voltage for so shifting the phase of the potential impressed on the grid of the space discharge device with respect to the potential impressed on the plate as to maintain the rectified voltage constant. The heater for the silver sulphide bridge arm may be connected to the output circuit of a space discharge device having the input circuit thereof controlled according to i the rectified voltage.

The single figure in the accompanying dra ing is a diagrammatic view of a regulated rectifier circuit constructed in accordance with the invention. 7

Referring to the drawing a supply circuit comprising conductors I and 2 is connected to a suitable source of alternating current 3. A load circuit comprising conductors 4 and 5 is connected to the supply circuit by means of two rectifier space discharge devices 6 and I and a transformer 8. The transformer 8 comprises a primary winding 9 and a divided secondary winding iii. The

space discharge device 6 is provided with an anode l I, a grid i2 and a cathode I3. The space discharge device I is provided with an anode H, a grid I5 and a cathode It. A battery I1 is floated across the load conductors 4 and 5 and a potentiometer i8 is provided for supplying potential to a control or regulator space discharge device iii. The load on the load conductors 4 and 5 may be of any suitable type and is diagrammatically illustrated as the adjustable resistance 20.

A phase shifting bridge circuit 2! is provided for connecting the grids l2 and it of the rectifier devices 6 and "l to the supply conductors I and 2 and for varying the phase of the potential on the grids with respect to the potential on the plates or anodes ii and i l of the devices 6 and i. The bridge 2i comprises a capacity arm 22, two inductive arms 23 and 2t in the form of a secondary winding of a transformer 25 and an arm 26 composed of silver sulphide which has a very pronounced negative temperature resistance coefficient. The arm 26 of-the bridge 2| is provided with a heating coil 2'! which is operated inversely in accordance with the rectified voltage on the load conductors 4 and 5. The silver sulphide arm 26 and the heating coil 21 are preferably enclosed in a vacuum tube in order not to beinfiuenced by ambient temperature changes. Transformer 25 is provided with a primary winding 28 which is connected across the supply conductors l and 2. Another secondary winding 29 is provided for heating the filament of the control space discharge device I9. Two

.opposite vertices of the bridge 2| are connected to the grid circuits of the rectifier space discharge devices 6 and! by means of a transformer 30..

The control space discharge device I9 is provided with an anode 3lconnected to the load conductor 4, a screen grid 32 connected to a tap from the potentiometer It, a control grid 33 confalls below normal value.

nected to a tap from the potentiometer l8 and a filament 34 which is heated by means of the secondary winding 29 on the transformer 25. The

controlgrid circuit for the control tube l9 may be traced from the grid 33 through a portion of the potentionmeter l8, load conductor 5, and the heating coil 21 to the filament 34 of the device 19. The drop caused by the heating coil 2'! insures suflicient drop so that the grid 33 has a negative potential impressed on it with respect to the filament 34.

The space discharge devices 6 and l which are preferably gas-filled tubes operate as a full-wave rectifier for supplying rectified current to the battery I? and the load circuit. If the voltage of this rectified current varies for any reason as for variation in supply circuit voltage or variat ons in load, the phase of the potential on the grids i2 and MS with respect to the potential on the plates ii and it is varied to control the rectified voltage. Varying of the phase on the grids l2 and i5 with respect to the potentials on the plates H and it is eifected by controlling the temperature of the silver sulphide arm 26 oi the phase shifting bridge 2i. The temperature of the silver sulphide arm 26 is controlled by the heater coil El which is included in the output circuit of the control tube i9. The circuit for the heating coil 2! may be traced from the negative load circuit conductor '5 through the heating coil 21, cathode 34 and anode iii of the tube is to the positive supply conductor l of the load circuit. The control grid E3 of the control tube is! has a negative potential impressed on it with respect to the filament 84 and serves to so control space discharge device it as to heat the coil ill inversely in accordance with changes of rectified voltage on the load condoctors 3 and i the rectified voltage on the supply conduc tors :3 and t; is increased, the negative potential on grid 33 will be increased to decrease the current fiow through the heater 2? and accordingly decrease the heating of the silver sulphide bridge arm "lhis increases the resistance of the arm fit for so changing the phase of the potential impressed on the grids it and i5 with respect to the potential impressed on the plates II and i l of the rectifier devices it and l as to reduce the rectified voltage on the load conductors l and An opposite effect takes place if the rectified voltage The above-described operation of the phase shifting bridge 2i having arm composed of silver sulphide continues under the control of the space discharge device is to maintain the rectified voltage substantially constant.

Modifications in the circuits and in the arrangement and location of parts may he made within the spirit and scope of the invention, and such modifications are intended to be covered by the appended claims.

W hat is claimed is:

1. In combination, an alternating current supply circuit, a load circuit, two three-element rectifier devices connected between the supply circuit and the load circuit for supplying rectified current to the load circuit, means comprising a phase shifting bridge circuit connected between the supply circuit and the grids of said devices, one arm of said bridge being composed of silver sulphide having a negative temperature resistance coeflicient and an extended resistance range, a coil for heating said am of silver sulphide, a space discharge regulator device provided with a control grid and having a potential impressed on Q aooasaa said grid according to the load circuit voltage, means for impressing the potential across said heating coil on said grid of the regulator device in opposition to the load circuit voltage, and means comprising said regulator device for heating said coil inversely according to the load circuit voltage to control said bridge and maintain the rectified voltage constant from no load to full load.

2. In combination, a load circuit, means comprising a three-element rectifier device for supplying rectified current to said load circuit, a phase shifting bridge connected to the grid circuit of said device for varying the phase of the grid potential with respect to the anode potential oi said device, said bridge having one arm composed of silver sulphide having an extended resistance range, and means for heating said silver sulphide arm inversely according to the voltage across said load circuit to control said bridge and maintain the rectified voltage constant from no load to full load.

3. In combination, an alternating current supply circuit, a load circuit, a storage battery connected across said load circuit, means comprising two three-element rectifier devices connected to said supply circuit for supplying rectified current to said load circuit, a phase shifting bridge connected to said supply circuit and having one arm composed of silver sulphide, said silver suiphide am having an extended resistance range, two vertices of said bridge being connected to the grid circuits of said devices, and means for heating said arm of silver sulphide inversely according to the potential across said load circuit to control the rectified voltage from no load to full load.

l. in a regulatedrectifier, two threeelement space discharge devices, a transformer connected to alternating current supply circuit, a load circuit so connected to a secondary winding of said transformer by said devices as to be sup- "plied with rectified current, a battery floated across said load circuit, means comprising a phase shifting bridge having one arm composed of silver sulphide having an extended resistance range for controlling the phase of the potential impressed on the grids of said devices with respect to the potential on the anodes of said devices to control the rectified voltage, and means comprising a heating coil for heating said arm of silver sulphide inversely according to the voltage across the load circuit to control said bridge circuit and maintain the rectified v0 tage constant from no load to full load.

5. in combination, an alternating current supply circuit, a storage battery, a load circuit connected to said cattery, means comprising two three-element rectifier devices for supplying rec til-led current to said battery from the supply circuit, a phase shifting bridge connected between said supply circuit and the grid circuits of said devices, one arm of said bridge being composed of silver sulphide having an extended resistance range, and means comprising a heating coil for heating said silver sulphide arm inversely according to the voltage across said battery to control the bridge circuit and maintain the rectified voltage constant from no load to full load.

6. In combination, an alternating current supply circuit, a load circuit, a storage battery floated across said load circuit, means comprising a three-element rectifier device for supplying rectified current tosaid load circuit from the supply circuit, a phase shifting bridge connected be-. tween said supply circuit and the grid circuit of aosasaa said rectifier device, said. bridge having an arm of silver sulphide with an extended. resistance range, a coil for heating said arm of silver sulphide, and means comprising a space discharge device controlled according to the potential across said load circuit for heating said coil inversely according to the load circuit voltage change to control said bridge and maintain the rectified voltage constant from no load to full load.

7. In combination, an alternating current supply circuit, a storage battery, a load circuit connected to said battery, means comprising a threeelement rectifier device for supplying rectified current to said battery from the supply circuit,

a phase shifting bridge having one arm composed of silver sulphide for connecting said supfrom said space discharge device for heating said silver sulphide arm to govern saidbridge and the rectifier device and maintain the loadcircuit voltage substantially constant from no load to full load.

ROBERT P. JUTSON.

DAVID E. TRUCKSESS. 

